Australian authorities have picked up more than 15,000 asylum seekers so far this year.

"We're certainly stretched - that's true," Mr Pezzullo told Sky News.

"But the vast majority of people are actually brought to Christmas Island safely."

Three asylum seeker boats were intercepted on Saturday with more than 340 people on board, while another vessel with 84 passengers was spotted on Sunday.

Indonesia is open to discussing the coalition's policy to turn back asylum seeker boats but its foreign minister Marty Natalegawa says any anti-people smuggling efforts must be in sync with bilateral and regional measures.

Dr Natalegawa said his country has had good communications with the Australian opposition about where it wants to take asylum seeker policy.

Earlier this month a joint communique from Mr Rudd and the Indonesian President stressed the importance of avoiding unilateral actions which might jeopardise a comprehensive regional approach or cause difficulties to any country.

The language was widely regarded as a rebuke of the coalition policy.

On Monday Dr Natalegawa said "unilateral action" could be troublesome if it was taken in total disregard to bilateral and regional settings.

"The task for all of us is to make sure that those efforts, the national efforts including of the type that parties here in Australia may be contemplating, ... are in sync or in synergy with bilateral and regional efforts, so that we don't cancel one another out," he told Sky News.

But he said it was yet to be seen whether Australia sending asylum seeker boats back to Indonesia would be "in sync".